If there is a proper Will made by the testator communicating her decision to transfer her immovable and movable property in the manner mentioned in the Will in favor of one or more beneficiaries, then there is no question of the excluded legal heirs to claim a share in the property already bequeathed in the Will.

Also there is no question of intestate succession if the property had been transferred by a testamentary disposition,. therefore to acquire the properties bequeathed in the Will, there is no necessity for listing out the legal heirs of the deceased. 

Registration of will is optional 

on demise of mother , father and children would be class 1 legal heirs 

If it is registered WILL then in future there will be no problem. (its mandatory to registered WILL) but for safer side its good practice to registered a WILL.

If its not registered then the probate is compulsory if any one legal heirs takes the objections against non registered of WILL.

Husband is the immediate legal heirs of wife's property and then children.

notary and registration not required

legal heirs of the mother are her husband and children

Dear Sir/Ma'am,

There is no need for registration of will and in your case, the legal heirs would be the father and your children.

Thank You

- As per law, registration of a WILL is not mandatory , and it can be written in the presence of two witnesses. 

- If there is chances of dispute , then probate of WILL is suggested .

- Further after the death of mother , her property would be devolved upon all her legal heirs equally including your father if alive and children. 

1.Even without notarisation, will of a person is valid if it has been executed as per law sifgning before two witnesses etc. However, wills are notarised, registered to establish that those have not been executed by the beneficiaries under coercion.

2. The sons, daughters (including the sons and daughters of her predeceased children) and husband are the legal heirs of a female Hindu as per Hindu Succession Act, 1956.

Yes. But registration is better